Manganese-doped ZnS quantum dots (QDs) stabilized by cysteamine hydrochloride were successfully synthesized. Their thorough physicochemical characteristics were acquired using UV-Vis absorption and photoluminescence spectroscopy, X-ray diffraction, dynamic light scattering (DLS), transmission electron microscopy (HR-TEM), energy dispersive spectroscopy (EDS) and Fourier transform infrared (FT-IR) spectroscopy. The average particle size, derived from HR-TEM, was 3.1nm, which agrees with the hydrodynamic diameter acquired by DLS, that was equal to 3-4nm, depending on ionic strength. The quantum dots also exhibited a large positive zeta potential varying between 75 and 36mV for ionic strength of 10 and 10M, respectively (at pH 6.2) and an intense luminescent emission at 590nm. The quantum yield was equal to 31% and the optical band gap energy was equal to 4.26eV. The kinetics of QD monolayer formation on silica substrates (silica sensors and oxidized silicon wafers) under convection-controlled transport was quantitatively evaluated by the quartz crystal microbalance (QCM) and the streaming potential measurements. A high stability of the monolayer for ionic strength 10 and 10M was confirmed in these measurements. The experimental data were adequately reflected by the extended random sequential adsorption model (eRSA). Additionally, thorough electrokinetic characteristics of the QD monolayers and their stability for various ionic strengths and pH were acquired by streaming potential measurements carried out under in situ conditions. These results were quantitatively interpreted in terms of the three-dimensional (3D) electrokinetic model that furnished bulk zeta potential of particles for high ionic strengths that is impractical by other experimental techniques. It is concluded that these results can be used for designing of biosensors of controlled monolayer structure capable to bind various ligands via covalent as well as electrostatic interactions.
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http://dx.doi.org/10.1016/j.jcis.2017.04.059 | DOI Listing |
Digit Health
December 2024
School of Nursing, University of Northern British Columbia, Prince George, BC, Canada.
Background: During the COVID-19 pandemic, governments across the world implemented processes and policies to limit the spread of COVID-19, especially in long-term care (LTC) homes. This led to changes in technology use for persons living in LTC homes, their families and friends, as well as the paid workforce dedicated to caring for them.
Objective: The study describes the role of technology and its impact on the experiences of LTC staff working in northern and rural areas in Western Canada during COVID-19.
Gait initiation is a fundamental human task, requiring one or more anticipatory postural adjustments (APA) prior to stepping. Deviations in amplitude and timing of APAs exist in Parkinson's disease (PD), causing dysfunctional postural control which increases the risk of falls. The motor cortex and basal ganglia have been implicated in the regulation of postural control, however, their dynamics during gait initiation, relationship to APA metrics, and response to pharmacotherapy such as levodopa are unknown.
View Article and Find Full Text PDFNeurol Genet
February 2025
Department of Neurology and.
Objectives: To report a case of adult-onset non-dystrophic myotonia complicated by recurrent episodes of laryngospasm.
Methods: The patient is a 35-year-old man who was admitted to our hospital for recurrent episodes of apnea requiring endotracheal intubation with mechanical ventilation. He underwent extensive evaluation, including EMG, laryngoscopy, muscle biopsy, and genetic testing, which revealed a diagnosis of non-dystrophic myotonia.
Fluids Barriers CNS
December 2024
School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette, 47907, IN, USA.
The importance of optimizing intrathecal drug delivery is highlighted by its potential to improve patient health outcomes. Findings from previous computational studies, based on an individual or a small group, may not be applicable to the wider population due to substantial geometric variability. Our study aims to circumvent this problem by evaluating an individual's cycle-averaged Lagrangian velocity field based on the geometry of their spinal subarachnoid space.
View Article and Find Full Text PDFNeuromodulation
December 2024
Institute of Science and Technology for Brain-inspired Intelligence, Fudan University, Shanghai, China; Ministry of Education Frontiers Center for Brain Science, Fudan University, Shanghai, China; Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China; Academy for Engineering and Technology, Fudan University, Shanghai, China. Electronic address:
Objective: This study aims to facilitate the translation of innovative closed-loop deep brain stimulation (DBS) strategies from theory to practice by establishing a research platform. The platform addresses the challenges of real-time stimulation artifact removal, low-latency feedback stimulation, and rapid translation from animal to clinical experiments.
Materials And Methods: The platform comprises hardware for neural sensing and stimulation, a closed-loop software framework for real-time data streaming and computation, and an algorithm library for implementing closed-loop DBS strategies.
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